This study investigated the effects of nicotine levels on cigarette smoking and nicotine replacement on attention, memory and cravings in smokers. Another aim of the study is to examine if smokers or non-smokers exhibit higher levels of social anxiety and stress levels. Research has suggested that nicotine may enhance both short term memory and attention, but little research has been done on the different doses administered and its effect on cognitive tasks the current study had 103 participants (N=103). There where fifty two participants that took part in the cognitive tasks and completed the questionnaires on cravings, anxiety and stress, fifty two non-smokers also completed the questionnaires. The overall results showed that the higher the nicotine levels, the faster the reaction time was in the attention task. It showed no significant difference in memory or accuracy. With regards to cravings, a significant difference was seen between the acute administration and the nicotine replacement therapy. Nicotine replacement seemed to satisfy cravings better than the acute cigarette. The final part of the results showed that Non-smokers and smokers seen no significant difference between anxiety levels, stress levels and positive, negative moods, but when it came to social anxiety, a higher rate was found in non-smokers.